1. Field of Invention
This invention relates generally to motor vehicle racks used to carry large, burdensome items such as ladders, pipes, and cable. More specifically, this invention relates to such racks which can be moved between two positions, [1] a first secured position generally utilized when the vehicle is in motion wherein the rack is securely disposed above the motor vehicle and the item is secured on the rack and [2] a second accessible position generally utilized when the item is being loaded and unloaded from the rack wherein the rack is adjacent to one side of the motor vehicle.
2. Related Art
A number of different racks exist in the prior art. Illustrative of such movable racks are U.S. Pat. No. 5,058,791 issued to Henriquez et al. on Oct. 22, 1991; U.S. Pat. No. 5,297,912 issued to Levi on Mar. 29, 1994; and U.S. Pat. No. 5,398,778 issued to Sexton on Mar. 21, 1995.
Each invention described in the listed patents includes a number of pivot points and/or rotating elements. Rotating elements and pivot points are inherently weak points in a design. Thus, it would be beneficial to the art to provide a rack having a minimal number of pivot points and rotating elements thereby increasing the overall strength of the rack.
In addition, none of the racks described in the listed patents are adjustable to securely carry items, specially ladders, having different widths. Thus, it would be beneficial to the art to provide a rack which is adjustable enabling it to securely carry ladders and other items having different widths.
Furthermore, the great majority of prior art racks that are movable between a secured position and an accessible position experience an instability problem as the rack is moved between the two positions. The instability problem is caused by the sudden extra weight contributed by the ladder once the center of gravity of the ladder moves "overcenter". This sudden extra weight provides an abrupt "jerk" on the operator's hold which may cause the operator's hold on the pivoting arm of the rack to slip, potentially resulting in property damage to the ladder, rack, and/or vehicle. Thus, it would be beneficial to the art to provide a rack which does not experience the instability problem experienced by prior art racks.
Finally, a number of different types of work vehicles exist, including vans and pick-up trucks, most of which have the need for a rack. Each vehicle type has different overall dimensions. In addition, obvious structural differences exist between pick-up trucks and vans which affect the placement and attachment of a rack to the vehicle. Thus, it would be beneficial to the art to provide a rack that is adjustable to fit a large number of vehicle types.